Structural abnormalities affecting enamel and dentine

Question 1

What is the most common defect?

Answer 1

Amelogenesis imperfecta

Question 2

Abnormalities from dental lamina formation stage

Answer 2

Hypodontia
Supernumerary teeth
Double teeth
Odontomes
Odontogenic tumours/keratocyst

Question 3

Histodifferentiation stage

Answer 3

Regional odonto-dysplasia

Question 4

Morphodifferentiation (size and shape)

Answer 4

Macrodontia
Microdontia
Dens invaginatus/evaginatus
Talon cusp
Taurodontism

Question 5

Matrix deposition

Answer 5

Amelogenesis imperfecta
Dentinogenesis imperfecta
MIH
Chronological enamel hypoplasia
Fluorosis
Dentine dysplasia

Question 6

Eruption and root development

Answer 6

Natal and neonatal teeth
Ectopic eruption
Delayed eruption
Transposition
Impactions

Question 7

Amelogenesis imperfecta pattern of inheritance

Answer 7

sporadic
almost all teeth are affected to more or less the same extent
developmental condition
genomic in origin
affects the structure and clinical appearance of enamel
associated with morphologic or biochemical changes elsewhere in the body

Question 8

What are the changes at the formation stage?

Answer 8

Matrix deposition is decreased - thin enamel = quantitative defect

Question 9

What are the changes at calcification stage?

Answer 9

Matrix mineralisation - quality defect

Question 10

What are the changes at the maturation stage?

Answer 10

Crystals enlarge/mature - quality defect

Question 11

What is hypoplasia?

Answer 11

Little enamel

Question 12

What is hypomineralisation?

Answer 12

Normal enamel but minimal mineralisation

Question 13

What are the characteristics of hypoplastic enamel?

Answer 13

pitted
hard enamel
reduced amount of enamel

Question 14

What are the characteristics of hypo mineralised enamel?

Answer 14

white to yellow opacities
soft, porous enamel
poor quality enamel
bonding affected

Question 15

Diagnostic history questions

Answer 15

FH?
Are all teeth affected in same manner/extent?
Any childhood illnesses during first 3y?
F history - swallowing toothpaste
Maternal issues, birth issues
Pedigree chart
Radiographs
Clin exam

Question 16

Other issues associated with AI

Answer 16

Accelerated tooth eruption
Impacted perm teeth
Ectopic eruption - second molars
Agenesis of second molars
AOB - 50% in hypoplastic AI
31% in hypomineralised AI
60% in hypocalcified AI

Question 17

Conditions associated with AI?

Answer 17

Tricho-dento-osseous syndrome - v curly hair in infancy and brittle bones

Cone-rod dystrophy - eventually leads to blindness

Taurodontism - dpt

Nephrocalcinosis

Question 18

Associated issues with AI

Answer 18

Lifelong tx needed
Aesthetic needs
Ectopic eruptions of impacted teeth
Psychological considerations
Sensitivity
Tooth wear and dysfunction - loss of vertical dimension which needs to be preserved
Bonding issues
Malocclusion

Question 19

Management of AI

Answer 19

Address pt concerns
Prep patients for long term tx
Tx depends on the type of defect
3m appl of F
Perm restorations when all dentition erupted
Crowns to prevent breakdown and maintain OVD

Question 20

Anterior teeth management

Answer 20

Microabrasion and bleaching
Composites - 5% NaClO if poor bonding

Question 21

Posterior teeth management

Answer 21

PMC, onlays, XLA, endo (less common)

Question 22

Dentogenesis imperfecta

Answer 22

1/6000-8000
Affects dentition exclusively
Associated with systemic conditions
Autosomal dominant pattern - 1 copy of gene needed to cause disorder
Can be associated with osteogenesis imperfecta if type 1 Di

Question 23

What mutations cause DI 1

Answer 23

Osteo imp association
COLIA1 and COLIA2 gene

Question 24

What mutations cause D1 2 and 3

Answer 24

DSSP gene

Question 25

Manifestations of DI 1

Answer 25

Ost Imp Teeth appear amber and translucent with attrition Radiographs - short constricted roots and dentine hypertrophy leading to pulpal obliteration Some teeth show total pulpal obliteration whilst on other the dentine appears normal MRONJ, bisphosphonates = rare in children

Question 26

Manifestations of DI 2

Answer 26

2 + 3 appear in people without inherited disorders type 2 - bulbous crowns and are typical features with marked cervical constriction. normal teeth are never seen Hearing loss

Question 27

Manifestations of DI 3

Answer 27

Clin features are variable and resemble those seen in DG 1 and 2 but primary teeth show multiple pulp exposures Radiographic appearance = shell teeth which appear hollow due to hypertrophy of dentine

Question 28

Management issues with DI

Answer 28

Aesthetics Function Psychological considerations Management aims remain the same as AI

Question 29

How to manage primary teeth

Answer 29

SSX Composite strip crowns Overdentures XGA

Question 30

How to manage permanent teeth

Answer 30

Anteriors - composite microabrasion/bleaching overdentures Posteriors PFM Cast gold inlays

Question 31

Radiographic features of DI

Answer 31

Enamel/dentine radiolucency normal Bulbous crown Constricted short roots Pulp canal obliteration (PCO) Pinched teeth at cervical margins Thin, spindly roos Short ADJ = not defined Taurodontism, long horned pulp chamber

Question 32

Bisphosphates in Osteogenesis imperfecta

Answer 32

Inhibit bone resorption Oral and IV preps Small blood vessels affected MRONJ Limited bone healing Increased susceptibility to infection 2-8 years Complete all dental tx in children before prescribing Post prescribing - non surgical tx if possible and CHX mouthwash pre and post of +/- ABs